IB ESS SL case studies
IB ESS SL · Put your knowledge to work in context.
IB Environmental Systems and Societies Standard Level (ESS SL) is a transdisciplinary DP course that pairs natural-science content with social and economic analysis, so candidates learn to treat environmental issues as systems problems rather than isolated facts. It suits students who want a science-flavoured subject without committing to a single laboratory science, and who are willing to argue from evidence in writing. The IB ESS SL case studies are 5 cases and about 4,287 words.
1Kestrel Ridge: deer, wolves and a missing trophic level
Kestrel Ridge Reserve covers 1,200 ha of temperate oak forest. The last wolf was shot in 1962.
796 words, about 4 min2Harlowheath metapopulation: corridor or patch restoration on a fixed budget
The Harlowheath silver-spotted skipper occupies six patches of lowland heather separated by conifer plantation and improved pasture. Survey data (area / adult butterflies / total butterfly species) are: P1 210 ha / 480 / 34; P2 95 ha / 210 / 27; P3 60 ha / 140 / 22; P4 22 ha / 0 / 14, with 6 adults recorded in 2015; P5 11 ha / 8 / 9; P6 4 ha / 0 / 5.
833 words, about 4 min3Lake Vellore: hitting a phosphorus target with a legacy in the sediment
Lake Vellore is an 8.4 km² reservoir supplying 190,000 people and hosting a cage farm producing 1,200 t of tilapia a year. August monitoring gives total phosphorus (TP) 45 µg/L, chlorophyll a 22 µg/L, Secchi depth 0.9 m, and hypolimnetic dissolved oxygen 2.1 mg/L during a two-week cyanobacterial bloom.
824 words, about 4 min4Zeravshan irrigation district: salinity, sodicity and drainage
The Zeravshan district has 4,600 ha of irrigated cotton and wheat in a semi-arid lowland with 210 mm annual rainfall and 1,850 mm pan evaporation. Water arrives by unlined canal; canal seepage and flood irrigation have raised the water table from 3.5 m in 2005 to 1.9 m in 2024.
907 words, about 5 min5Island grid: how much of a 20 MW solar array is actually usable
An island nation of 84,000 people generates 62 GWh of electricity a year from six diesel generators, with peak demand of 45 MW and a daytime minimum of 24 MW. Diesel fuel costs US 0.28 per kWh and the utility emits 0.72 t CO2 per MWh generated.
927 words, about 5 min